<!DOCTYPE HTML>
<html>
<!--
https://bugzilla.mozilla.org/show_bug.cgi?id=654550
-->

<head>
  <title>Test for Bug 654550</title>
  <script type="text/javascript" src="/tests/SimpleTest/SimpleTest.js"></script>
  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css"/>
  <script type="text/javascript" src="manifest.js"></script>
</head>
<body>
<a target="_blank" href="https://bugzilla.mozilla.org/show_bug.cgi?id=654550">Mozilla Bug 654550</a>
<pre id="test">
<script class="testbody" type="text/javascript">

  /* Test for Bug 654550 */

  // Parallel test must be disabled for media.video_stats.enabled is a global setting
  // to prevent the setting from changing unexpectedly in the middle of the test.
  PARALLEL_TESTS = 1;
  SimpleTest.waitForExplicitFinish();
  var manager = new MediaTestManager;

  function checkStats(v, aShouldBeEnabled) {
    if (aShouldBeEnabled) {
      ok(v.mozParsedFrames != 0,
         "At least one value should be different from 0 if stats are enabled");
    } else {
      ok(!v.mozParsedFrames,
        "mozParsedFrames should be 0 if stats are disabled");
      ok(!v.mozDecodedFrames,
        "mozDecodedFrames should be 0 if stats are disabled");
      ok(!v.mozPresentedFrames,
        "mozPresentedFrames should be 0 if stats are disabled");
      ok(!v.mozPaintedFrames,
        "mozPaintedFrames should be 0 if stats are disabled");
    }

  }

  function ontimeupdate_statsEnabled(event) {
    var v = event.target;
    v.removeEventListener('timeupdate', ontimeupdate_statsEnabled, false);
    checkStats(v, true);
    SpecialPowers.popPrefEnv(
      function() {
        v.addEventListener("timeupdate", ontimeupdate_statsDisabled);
    });
  }

  function ontimeupdate_statsDisabled(event) {
    var v = event.target;
    v.removeEventListener('timeupdate', ontimeupdate_statsDisabled, false);
    checkStats(v, false);
    removeNodeAndSource(v);
    manager.finished(v.token);
  }

  function startTest(test, token) {
    var v = document.createElement('video');
    v.token = token;
    v.src = test.name;
    // playback may reach the end before pref is changed for the duration is short
    // set 'loop' to true to keep playing so that we won't miss 'timeupdate' events
    v.loop = true;
    manager.started(token);
    SpecialPowers.pushPrefEnv({"set": [["media.video_stats.enabled", true]]},
      function() {
        v.play();
        v.addEventListener("timeupdate", ontimeupdate_statsEnabled);
    });
  }

  SpecialPowers.pushPrefEnv({"set": [["media.video_stats.enabled", false]]},
    function() {
      manager.runTests(gVideoTests, startTest);
  });

</script>
</pre>
</body>
</html>
